Thermostatic damper control



May 8, 1956 C. B. COSELMAN THERMOSTATIC DAMPER CONTROL Filed July 12,1955 Fig./

2 Sheets-Sheet 1 Clinton 8. Case/man INVENTOR.

THERMOSTA'IIC DAMPER CONTROL 2 Sheets-Sheet 2 Filed July 12, 1955 Fig.4

Fig.5

I In Clinton 8. Case/man INVENTOR.

THERMOSTATIC DAMPER CONTROL Clinton B. Coselman, Seattle, Wash, assignorto C. B. Coselman, Incorporated, Seattle, Wash, a corporation ofWashington Application July 12, 1955, Serial No. 521,601

4 Claims. (Cl. 236-96) This invention relates in general to new anduseful improvements in heater controls, and more particularly to animproved thermostatic damper control for heaters,

The primary object of this invention is to provide an improvedthermostatic damper control primarily intended for use in conjunctionwith residence type heaters whereby heaters, especially those of thewood burning type, may have the draft thereof automatically controlledso that the heat emitted from such heaters may be controlled within ageneral and desired range.

Another object of this invention is to provide an improved thermostaticdamper control which is so constructed whereby it may be easily attachedand removed from casings of heater so that the heat emitted from thefireboxes of such heaters may effectively be controlled by varying thedraft thereon through the use of the thermostatic damper control.

Still another object of this invention is to provide an improved heaterconstruction which includes a firebox having a draft fitting with theinlet thereof controlled by a damper, the draft fitting being of a sizeto permit the entrance of sufiicient air to accomplish the orderlycombustion of gases within the firebox so as to prevent explosions, andfurther, when combustion is not possible, to pass those gases out of thesmokepipe', thereby preventing the accumulation of sufficient gases tocause an explosion when combustion starts.

A further object of this invention is to provide an improved draftconstruction for heaters of the type including a firebox and a spacedcasing, there being connected to the firebox within the casing a draftfitting controlled by a damper and there being mounted on the casingbetween the casing and the firebox a thermostatic control responsive tothe heat within the casing for controlling the actuation of the damperwhereby'a desired heat may be maintained.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

Figure l is a side elevational view of a heater utilizing thethermostatic damper control which is the'subject of this invention, aportion of the casing of the heater being broken away in order to showthe specific details of the damper and the relationship of the dampercontrol means with respect'thereto;

Figure 2 is a top plan view of the heater of Figure 1 and shows thegeneral relationship of the components thereof;

Figure 3 is an enlarged fragmentary vertical sectional view takensubstantially upon the plane indicated by the section line 3-3 of Figure1 and shows the specific manner in which a chain for actuating thedamper is connected to a drive member;

nited States Patent" 2,144,589 Patented May 8, 1956 ice Figure 4 is anenlarged fragmentary top plan view of the heater immediately above thedamper control and shows the general details of both the thermostaticcontrol assembly'and the damper;

Figure 5 is an enlarged fragmentary horizontal sectional view takensubstantially upon the plane indicated by the section line 5--5 ofFigure l and shows the specific details of the draft fitting includingthe damper;

Figure 6 is an enlarged fragmentary vertical sectional view takensubstantially upon the plane indicated by'the section line 66 of Figure1 and shows more specifically the details of the draft fitting and therelationship of the damper thereto; and Figure 7 is an enlargedfragmentary verticalsectional view taken substantially upon the planeindicated by the section line 7--7 of Figure 4 and shows the specificmounting of the thermostatic member of the damper control.

Referring now to the drawings in detail, it will be seen that there isillustrated in Figures 1 and 2 a residence type heater, preferably ofthe wood burning type, which is referred to in general by the referencenumeral 10. The heater 10 includes a firebox 12 which is provided at thefront end thereof with a fire door 14. Extending upwardly from thefirebox 12 at one side thereof is a smokepipe 16. The heater 10 alsoincludes a casing which is referred to in general by the referencenumeral 18. The casing 18 extends about the firebox 12 at the two sidesand rear thereof, as is best illustrated in Figure 2,- the casing havinga lower opening.

In orderto support the combustion of the burnable material within thefirebox 12, there is formed in the lower part of one side of the firebox12 a draft opening 29. Secured to the firebox 12 in overlying relationto the draft opening 20 is a draft fitting 22. The draft fitting 22includes a generally rectangular inhorizontal cross-section upperportion 24 which terminates in a diverging lower portion 26. The draftfitting 22 includes outwardly projecting mounting flanges 28 which (aredisposed in face-to-face engagement with the firebox 12 and is securedthereto by suitable nut and bolt fasteners 30. v

The draft fitting 22 isprovided with an open" upper end 32. Aligned withthe open upper end 32 and controlling the downward flow of airtherethrough is a damper 34. The damper 34 includes'a pair of upwardlyprojecting ears 36 at opposite ends thereof which are mounted on a shaft38. The shaft 38 extends'across the upper end of the draft fitting 22and is carried by a pair of mounting. brackets 40. The mounting brackets40 are secured to opposite ends of the draft fitting 22 and adjustablyretained in vertically selected positions by fasteners 42, the fasteners42 extending through vertical slots 44 in the mounting brackets 40, asis best illustrated in-Figure 6.

Disposed generally vertically above the. draft fitting 22 and secured tothe" inner surface of the casing 18 is a thermostatic damper control'which is referred to in general by the reference. numeral 46. Thethermostatic damper control 46 includes an elongated mounting plate 48which is detachably secured to the inner surface of the casing 18 bymeans-of suitable nutand bolt fasteners 50. Thus, the entirethermostaticdamper control 46 may be quickly and easily positioned andremoved, as is deemed necessary.

Carried by the central portion-of the mounting plate 48 is ahorizontally U-shaped cross-sectional mounting bracket 52 which projectsinwardly towards the fire-v box 12. Carried by. the mounting bracket 52is a drive shaft 54 which is horizontally disposed. Mounted on the driveshaft 54 for rotation therewith is a drive sprocket 56. Entrained overthe drive sprocket 56 is a drive chain 58 which is secured to the drivesprocket 56 by a pin As is best illustrated in Figure 3, the lowerportions of the drive chain 58 are crossed, and the lower ends thereofare connected to the upper surfaces of the damper 34, as is bestillustrated in Figure 6.

An end of the drive shaft 54 projects beyond the mounting bracket 52.Mounted on the projecting end of the drive shaft 54 is a spiralthermostatic member 60. The thermostatic member 6b, as is bestillustrated in Figure 7, has an inner end thereof secured to the driveshaft 54. The outer end of the thermostatic member 60 is in the form ofa box-shaped member 62 Which extends from the drive shaft 54 and isselectively positioned.

Carried by an end of the mounting plate 48 is a generally L-shapedmounting bracket 64 whose configura tion is best illustrated in Figures3 and 4. Carried by the mounting bracket 64 in alignment with the driveshaft 5-4 and projecting away therefrom is a mounting shaft 66. Mountedon the mounting shaft 66 for relative rotation and being disposedimmediately adjacent the mounting bracket 64 is a rotatable controlmember 68. The control member 68 is spaced from the mounting bracket 64by means of a washer 7i) and is urged. into frictional engagement withsuch Washer 70 by means of a spring 72 disposed between a pair ofcup-shaped Washers 74. One of the Washers 74 bears against the controlmember 68, and the spring 7'2 is tensioned by means of adjustable nutmembers 76 threadedly engaged on the mounting shaft 66.

As is best illustrated in Figures 4 and 7, there is carried by thecontrol member 68 in eccentric relation with respect to the mountingshaft 66 a connecting rod 7&3. The connecting rod 78 is disposed inparallel relation with respect to the shafts 54 and 66 and has an endportion thereof received in the box-like portions 62 of the thermostaticmember 6 In order that the control member 68 may be utilized in settingthe thermostatic member 60, the casing 18 is provided with an opening:80 through which a portion of the control member 68 projects. Theperiphery of the control member 63 is provided with suitable indicia 82.to indicate the desired heat setting. Further, the periphery of thecontrol member 68 is provided with suitable notches 84 to facilitateturning thereof. Rotation of the control member 68 is limited by meansof a stop member 86 which is engageable with the inner surface of thecasing 18, the stop member being best illustrated in Figure 4.

In the operation of the present invention, control of the heat emittedby the firebox 12 is maintained through the use of the thermostaticdamper control 46. As pointed out above, the thermostatic member 60' isset by means of the control member 63. Inasmuch as the thermostaticmember 60 is disposed adjacent the firebox 12, the heat emitted from thefirebox 12 will act directly upon the thermostatic member 60 to effectoperation thereof. As the thermostatic member fill expands or contracts,it will result in the pivoting of the damper 34, to the proper positionto furnish the necessary draft to the firebox 12 to maintain the desiredheat.

In order that the fire in the firebox 12 will continue to burn eventhough the thermostatic damper control d6 results in the closing of theinlet opening 1'52, there is formed in the damper 34, as is bestillustrated in Figure 5, a small vent opening 88. The vent opening 33 isselectively closed by means of a small damper 9t) pivotally connected tothe upper surface of the damper 34 by means of a pivot pin 92.

It is pointed out at this time that the relationship of the controlmember 68 with respect to the thermostatic member 60 is such that thecontrol member 68 at the extremes of its positions may completelyoverride the thermostatic member 60. Thus, the damper 34 may bepermanently retained in a closed position, irrespective of thetemperature changes, or may be retained in a completely open position,notwithstanding the heat generated by the fire in the firebox 12.

Referring now to Figure 1 in particular, it will be seen that the upperpart of the firebox 12 approximately opposite the smokepipe 16 isprovided with an opening 4 controlled by a rotatable damper 96. Thedamper 96 is manually controlled to permit a measured amount of air toenter into the firebox 12 to enable proper corn bustion of explosivegases. The incoming draft of air through the opening 94, because of itslocation in the upper part of the firebox 12 and opposite the smeltepipe16, both provides air for the combustion of the explosive gases thataccumulate naturally inside and at the top of the firebox l2, and alsoprovides a suitable draft for removing explosive gases out of thefirebox l2 and up through the smokepipe 16 in situations where no flameexists for combustion of such gases, thus preventing gas accumulation,as well as the ignition and explosion on appearance of flame in apreviously dormant fire. Continuous clearance of smoke from. the firebox12 is also accomplished, thus preventing smoke accumulation from issuingthrough the fire door 14 when opened.

it is pointed out that the dampers 34 and 96 do not work against eachother, but due to their relative locations, one at the top and the otherat the bottom of the firebox 12, function independent of coordinatingwith each other. it is also pointed out that the damper 96 isadjustable, enabling it to perform its function regardless of the amountof draft the chimney may be capable of producing.

in order that a relatively tight seal may be made between the damper 34and the draft fitting 22, the upper edges of sides of the draft fittingare provided with inturned flanges 98 which overlie the damper 34-.Further, secured against the fire wall, as is illustrated best in Figure6, is a stop bar 100. The stop bar 100 is positioned by fasteners H32and is engageable with the damper 34 to form a seal therewith.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly, all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention asclaimed.

What is claimed as new is as follows:

1. A heater construction comprising a firebox, a draft fitting on saidfirebox, a damper controlling the flow of air through said draftfitting, a casing spaced from said firebox, said casing enclosing atleast part of said firebox, said draft fitting and said damper, an airinlet at a lower end of said casing, means for controlling said dampersecured to said casing and positioned between said casing and saidfirebox, said means being carried by a mounting panel detachably securedto said casing. said means including a drive shaft, damper connectingmeans connecting said drive shaft to said damper, a thermostatic membermounted on said shaft and having one end anchored thereto, a mountingshaft spaced from said drive shaft, a control member rotatably mountedon said mounting shaft, a connecting rod carried by said control membereccentric to said mounting shaft, said thermostatic member having anopposite end connected to said connecting rod.

2. A heater construction comprising a firebox, a draft fitting on saidfirebox, a damper controlling the flow of air through said draftfitting, a casing spaced from said firebox, said casing enclosing atleast part of said firebox, said draft fitting and said damper, an airinlet at a lower end of said casing, means for controlling said dampersecured to said casing and positioned between said casing and saidfirebox, said means being carried by a mounting panel detachably securedto said casing, said means including a drive shaft, damper connectingmeans connecting said drive shaft to said damper, a thermostatic membermounted on said shaft and having one end anchored thereto, a mountingshaft spaced from said drive shaft, a control member rotatably mountedon said mounting shaft, a connecting rod carried by said control membereccentric to said mounting shaft, said thermostatic member having anopposite end connected to said connecting rod, said thermostatic memberbeing of a spiral configuration.

3. A thermostatic damper control comprising a mounting panel, a driveshaft, damper connecting means connecting said drive shaft to a damper,a thermostatic member mounted on said shaft and having one end anchoredthereto, a mounting shaft spaced from said drive shaft, a control memberrotatably mounted on said mounting shaft, a connecting rod carried bysaid control member eccentric to said mounting shaft, said thermostaticmember having an opposite end connected to said connecting rod.

4. A thermostatic damper control comprising a mounting panel, a driveshaft, damper connecting means connecting said drive shaft to a damper,a thermostatic member mounted on said shaft and having one end anchoredthereto, a mounting shaft spaced from said drive shaft, a control memberrotatably mounted on said mounting shaft, a connecting rod carried bysaid control member eccentric to said mounting shaft, said thermostaticmember having an opposite end connected to said connecting rod, saidthermostatic member being of a spiral configuration.

References Cited in the file of thispatent UNITED STATES PATENTS2,253,442 Montague Aug. 19, 1941 2,263,362 Logue Nov. 18, 1941 2,454,044Eggert Nov. 16, 1948 2,714,993 Gardiner Aug. 9, 1955

